Electrode material for rechargeable batteries and process for the preparation thereof

Abstract

There is provided a series of novel particulate stabilized lithiated compounds which can be utilized as cathodic materials in lithium ion battery cells. Each particle of the material defines an inner lithiated metal oxide core which acts as an intercalation cathode. A lithium ion conductor coating surrounds the core to stabilize the latter and to improve the electrochemical properties of the material.

1. A particular cathodic material for use in a rechargeable lithium electrochemical cell wherein each particle comprises:
 a lithiated transition metal oxide core functional as an intercalation cathode consisting of lithium nickel dioxide or lithium nickel cobalt dioxide having the formula LiNi 1-y Co y O 2  wherein y>0, or a mixture thereof, and a lithium ion conductor coated on each particle of said core said conductor having electron conductive properties and being functional to stabilize said core to thereby impart predetermined electrochemical properties to said cathodic material, wherein said lithium ion conductor is LiCo x Ni 1-x O 2  having a thickness between about 0.5 nm and about 5000 nm, and wherein x>y+0.1 for y<0.9, and x>0.1 for lithium nickel dioxide as a core.  
 
     
     
       2. The cathodic material as set forth in  claim 1  wherein said lithium ion conductor is LiCo x Ni 1-x O 2  having a thickness between about 1 nm and about 500 nm and x>0.1 for y<0.9, and x>0.1 for lithium nickel dioxide as a core. 
     
     
       3. A particulate cathodic material for use in a rechargeable lithium electrochemical cell wherein each particle comprises:
 a lithiated transition metal oxide core functional as an intercalation cathode consisting of lithium nickel dioxide or lithium nickel cobalt dioxide having the formula LiNi 1-y Co y O 2  wherein y>0, or a mixture thereof, and a lithium ion conductor coated on each particle of said core, said conductor having electron conductive properties and being functional in stabilize said core to thereby impart predetermined electrochemical properties to said cathodic material, wherein said lithium ion conductor is LiCo x Ni 1-x O 2  and wherein x>0 and x>y.